This are miscellaneous codes, but since you can use some of them to help to get stable fps, i will post them here.
The Alliance Alive - USA
Title ID: 00040000001CCD00
[3D Effect Permanently Deactivated]
003B6D90 00000000
[3D Effect Permanently Activated]
003B6D90 3F800000
[Fast change of view angle/camera]
0814E10C 00000001
[Normal change of view angle/camera]
0814E10C 00000002
I tried to locate the fps address on TAA but every time I failed. If anyone want to try it, on the Burning Realm, more specific, on Blue Oasis the fps drops from 30 to 20 (if you stay still, the map zooms out giving you a full view of the city and it's temporarily on 3D, in that moment the fps drops).
What caught my attention is that the frames drops even if you don't activate the stereoscopic 3D (or if you are playing it on a New 2DS XL). So after a little research, find a way to turn off completely the 3D. When you use the 3D Effect Permanently Deactivated code, the game achieve stable 30 fps (well, to be honest, it drops a little when the maps zooms in or out on cities but you can fix that with the Fast change of view angle/camera code , so i recommend to use both codes).
On the other hand, if you use the 3D Effect Permanently Activated code, you can actually play all the game on stereoscopic 3D. Most of the time the 3D looks good, but on some scenes and scenarios the stereoscopic 3D looks weird, one notable example is Hakurei Castle, inside of it, on the stairs that connect the floors of the castle. (You can use the 3D on this area, but i recommend to put the 3D slider on minimum. Otherwise, the effect will look strange, oversatured. The same issue occurs on other games, like on some boss fights of Thor: God of Thunder, when you put the 3D on maximum)
But this code has a severe downside: It impact to the fps on most of the game. On the world map, the fps drop from 30 to 20-15 and on some areas even less, 18-14 fps. On battle, frames also drop to 20 and when you do some heavy special attacks, like Omni-Rush or Five Dragon Strike, the game drops to 11 fps.
So you can imagine that playing using the stereoscopic 3D is no a pleasant experience, but in any case, is possible to do it.
Well, that's all. Sorry for the text wall.
PD: All this was tested on New 3DS, i have no idea how it runs on Old 3DS